Some 700,000 begonia flowers will fill Brussels' main square from Friday to form a vibrantly coloured flower carpet that will wither and brown by the end of the weekend.
The Belgian capital's Grand Place "is like a jewel box," said Annette Katz of the Brussels tourist office. "You put a beautiful carpet in a jewel box and that's magic."
Scarlet red, pure white, sunshine yellow, salmon pink and bright orange begonias are being pressed into the intricate pattern of a 17th century French carpet, balanced by the darker shades of purple dahlias, green grass and brown soil.
Work started Monday laying a plastic covering over the square's cobble stones and tracing a pattern for the volunteers to follow.
Supervisors went round Thursday checking that the right colour petals were being laid into the proper forms of flowers, crosses and acanthus leaves.
The flower carpet blossoms on the Grand Place every two years.
"It's much more difficult than previous years when there were bigger motifs," said volunteer Lieve Verplancke, one of 80 people spending a day wedging the flowers firmly into the twists and curves of the design.
Belgium is now one of the biggest exporters of begonia tubers, sending most of the flowers it grows abroad to the Netherlands, France and the United States.
Those that stay have a brief moment of fame for the three days and four nights of the flower carpet.